a) Field of the Invention
This invention relates to an automobile seat with a side-impact air bag accommodated within a seat back, and especially to an automobile seat which permits adjustments of position and direction of burst-out of an air bag as needed.
b) Description of the Related Art
In recent years, air bags have been attracting attention as safety measures for automobiles, and have already found wide-spread commercial utility. Significant popularity is observed especially with longitudinal-impact air bags, each type of which bursts out toward a driver from a location in front of the driver to cushion forward impact. In addition, developments of side-impact air bags (side air bags) have been under way, also resulting in the increasing commercial utilization of these. A side-impact air bag bursts out from a location to the side of an occupant to cushion striking of an automobile body, located on an outboard side of the occupant, against the occupant.
Such a side air bag is caused to burst out between a side body of an automobile and an occupant in the event of a side impact to cushion collision between the side body and the occupant. Due to an extremely short distance between the side body and the occupant, the side air bag is required to have a higher inflation responsiveness than a longitudinal-impact air bag. Moreover, it is also necessary to allow the side air bag to burst out to an appropriate position so that the cushioning of an impact against the occupant can be ensured.
A construction is proposed, for example, in Japanese Patent Application Laid-Open (Kokai) No. HEI 4-50052, in which a side air bag is arranged in a side portion of a seat back and the direction to which the side air bag bursts out is determined by setting the position of an inflator equipped with a detonator.
Another construction is proposed in Japanese Patent Application Laid-Open (Kokai) No. HEI 7-215159, in which a side air bag is also arranged in a side portion of a seat back and the direction to which of the side air bag bursts out is determined by guide means.
A further construction is proposed in Japanese Patent Application Laid-Open (Kokai) No. HEI 7-228213, in which the direction to which a side air bag bursts out is defined by a lid arranged over an opening of a seat back, through which the side air bag is allowed to burst out.
In each of the constructions disclosed in Japanese Patent Applications Laid-open (Kokai) Nos. HEI 4-50052 and HEI 7-215159, an opening through which the side air bag is allowed to burst out is also formed in the seat back, and a lid is also arranged over the opening.
However, each of the above-described conventional arts is of the construction where the side air bag bursts out through a lid-covered opening, the lid exposed through the surface of the seat back. It is therefore difficult to assure good external appearance. Moreover, the lid is formed of a material such as a resin of different nature and substantially different touch from that of the surface of the seat back so that the lid cannot be positioned on a front side of the seat back where it would come in contact with the seated occupant's body. Therefore the lid is arranged on a side wall of the seat back. As a consequence, the opening through which the side air bag bursts out is also arranged on the side wall of the seat back, leading to the problem that a limitation is imposed on the direction to which the side air bag bursts out.
There is, accordingly, a desire for a construction in which a side air bag is accommodated within a seat back without the arrangement of a lid different in nature from the surface of the seat back. In this case, however, the opening which was closed over by the lid obviously cannot be formed in the surface of the seat back. Namely, a seat back construction in which an opening is formed in a surface of the seat back without closing it with a lid or the like lacks commercial attraction.
Without such an opening in a seat back, the burst-out of the side air bag is interfered with by the seat back when a side air bag in the seat back is caused to expand by an inflator. This makes it difficult for the side air bag to burst out of the seat back. Even if the side air bag is allowed to burst out, there are problems that this burst-out tends to be low in responsiveness and is not easily controllable in direction.